The present invention relates to manipulating files in a computing environment.
Software applications create and manipulate files. Each file is characterized by a file type, which can be indicated to the operating environment by a file extension or MIME (Multipurpose Internet Mail Extensions) type. For example, TIFF files (Tagged Image File Format) have a MIME type of “image/tiff” and a “.tif” extension, while PDF files (Portable Document Format) have a MIME type of “application/pdf” and a “.pdf” file extension. In addition, some file types have a “magic number”: an initial sequence of bytes or data at the beginning of the file which only appears (or is likely to appear) in files of a particular type.
As used in this specification, the term file type can be a complex of different components. File type can include file extension (“.pdf”), MIME type or content-type (“application/pdf”) and/or “a magic number,” a special sequence of bytes that only appear inside files of a particular type. The different ways of indicating or determining file type are usually, but need not, be correlated. For example, a single MIME type can correspond to several file extensions, one file extension can be used by several MIME types, and file type determination by magic number detection is often unreliable.
In many operating environments, file types can be associated with a default application. For example, in a typical computer system installation, Microsoft PowerPoint® software available from Microsoft Corporation of Redmond, Wash. may open PowerPoint files, Adobe® Acrobat® software available from Adobe Systems Incorporated of San Jose, Calif. may open PDF files, etc. In most operating systems, such as the Macintosh® or Windows® environments, users can associate a specified application with a particular file extension or MIME type to make the specified application the default opener for the particular file extension or MIME type. In some cases, operating systems check for a default opener whenever a file is opened. When a default application has been specified, to use any other application to open a file a user must launch the other application separately and select the file from within that application, drag the file icon to the application icon or use another file opening method.
However, many files can be opened by more than one application. For example, files in the PSD format, which is the native file format of the Adobe® Photoshop® graphical editing software, can be opened by both Photoshop® software and Photoshop Elements® software, both available from Adobe Systems Incorporated. Similarly, a variety of different applications, including Adobe® Acrobat® and Acrobat® Reader® software, can open PDF files. Many applications make themselves the default opener for particular file types upon installation, overwriting settings for any previously defined default applications. To restore a previously defined default opener, the user may be required to manually reset the original settings, or even to reinstall the former default application. In some cases, an application checks whenever it is launched to determine if another application has taken its place as the default opener, and changes the settings to reestablish itself as the default opener.
Some file types can be used for multiple purposes. For example, tagged image file format (“TIFF”) files, having a MIME type of “image/tiff” and a “.tif” file extension, can be used for photographs and for multipage document images. While different applications might be the best default opener for a given use, only one of these applications can typically be designated as the default opener. The conflicts between competing applications can make it difficult for a user to ensure that the best application will be used to open a selected file. The user might also be unaware what the default opener is for the selected file.